A technology has been known which performs a liquid processing on a substrate by sequentially switching and supplying, for example, a chemical liquid and a rinsing liquid to a surface of a rotating substrate (e.g., a semiconductor wafer (referred to as a “wafer”)). When the liquid processing is completed, drying the substrate is performed by supplying a highly volatile drying liquid such as, for example, isopropyl alcohol (IPA) to the rotating substrate to replace the liquid remaining on the surface of the substrate with the drying liquid, and then, discharging the drying liquid (see, e.g., Japanese Laid-Open Patent Publication No. 2007-36180: Claim 4, paragraph 0087, and FIG. 3).
Meanwhile, when the humidity inside the processing container where the liquid processing is performed is high, a dew condensation may occur on the dried surface of the wafer. When a droplet attached to the surface of the wafer at the time of the occurrence of the dew condensation is dried at a later time, a watermark may be formed thereby contaminating the liquid-processed wafer, or a pattern on the surface of the wafer may, for example, collapse due to an action of the surface tension caused from the droplet.